#ifndef _LEFTIST_HEAP
#define _LEFTIST_HEAP

//left heap is not perfectly balanced.Actually, it tends to be very unbalanced

//Npl(X){Null Path Length} is the length of shortest path from X to a node without two child nodes
//Npl(NULL) == -1

//the nature of leftist heap, to each node of heap, left child' Npl should be same as right child's.
//It obviously tend to increase depth to the left node.

//the basic operation to leftist heap is merging.

#endif